Previously most spacing stick or lath placer machines, hereinafter collectively alternatively referred to as stick placers, incorporated a stick carrier such as a finger-like device, a shelf, or a vacuum lifting device. One example of a stick placer used for spacing lumber for drying purposes, which is the subject of U.S. Pat. No. 3,643,621, utilizes a plurality of single magazines having a placing device below each magazine. The device does not lend itself to automatic feed, and does not work effectively with thin lath used for transporting finished lumber packages. It may not easily be combined to place both spacing sticks and lath.
An example of a lath placer is the subject of U.S. Pat. No. 5,244,341. This device utilizes a rotary vacuum actuator that picks lath up from the top of a short curved magazine. The actuator rotates back from the magazine and drops the lath onto the lumber package. The device can not effectively deliver spacing sticks used for spacing lumber for drying and likely could not be used in a combined system for both lath and spacing sticks.
U.S. Pat. No. 3,968,886 teaches a device that likely could not be combined to successfully place both spacing sticks or lath using the same apparatus. The apparatus of U.S. Pat. No. 3,169,646 is designed for spacing sticks and could only capably handle either spacing sticks or, possibly, lath at any one time. No means is provided for positive placement of spacing sticks or lath.
One disadvantage of prior art machines addressed in the present invention is that given that the top surface of a lumber stack is rarely completely level or even because each piece of lumber is not exactly the same shape as the piece beside it, especially where lumber is often curve-sawn, a spacing stick or lath dropped onto that surface may bounce and consequently be misplaced. Thus it is an object of the present invention to accurately place sticks and lath, especially at the ends of the lumber stacks, where typically sawmills require a flush end face of the stack to reduce checking as the lumber stack is dried.
It is a further object of the present invention to produce an apparatus wherein delivery of sticks is automatic, maybe faster than with present installations so as to equal to the speed capabilities of known lumber stackers. Many methods of feeding sticks or lath may be employed for such delivery.
It is another object of the invention to produce an apparatus wherein the system can deliver spacing sticks and packaging lath, using the same apparatus to deliver sticks or lath to various predetermined position, with improved consistency and accuracy, with reduced probability of hang-ups or miss delivered spacing sticks.
It is still another object of the invention to provide a device that can be retro-fitted to existing lumber stackers without extensive changes.
It is further an object of the invention to allow for adjustability for a second lumber line at a first stick placing position, which eliminates the conventional use of one-foot stick placement spacing on a lumber package to allow for odd lengthed lumber packages.